Apparatus for preparing briquetted fuel for burning



Feb. 24, 1931. l.. B, GREEN' APPARATUS FOR PREPARING BRIQUETTED FUEL `FOR BURNING Filed Feb. 14. 1927 5 Sheets-Sheet l Feb. 24, 1931. L. B. GREEN 1,793,691

APPARATUS FOR PREPARING BRIQUETTED`FIUEL FOR BURNING Filed Feb. 14, 1927 5 Sheets-Sheet 2 L. B. GREEN i Feb. 24, 1931.

1,793,691 APPARATUS FOR PREPARING BRIQUETTED FUEL FOR BURNING Filed Feb. 14, 1927 5 Sheets-Sheet 3 Feb. 24, 1931.

L. B. GREEN APPARATUS FOR PREPARING BRIQUETTED vFUEL FOR BURNING Feb. 24, 1931. l.; B. GREEN y 1,793,591'

APPARATUS FOR PREPARING BRIQUETTED FUEL FOR BURNING Filed Feb. 14, 1927 `5 sheets-sheet 5 Patented Feb. 24, 1931 UNITED STATES PATENT OFFICE LEE B. GREEN, OF LAKEWOOD, OHIO, ASSIGN OR TO THE BORD'EN COMPANY, OF WARREN, OHIO, A CORPORATION OF OHIO APPARATUS FOR PREPARING BRIQUETTED FUEL FOR BURNING Application filed February 14, 1927. Serial No. 167,901.

This invention relates to an apparatus for iringbriquetted pulverized coal, and particularly a briquet of the character described in my co-pending application, Serial No.

' 5 149,799, filed November 20, '1926, entitled Method of preparing solid fuel for burning in pulverized form.

The machine of the present invention is designed for the burning of briquets, formed lo of pulverized coal together with a suitable binder, which materials are introduced into an ordinary briquetting machine and there mixed and pressed into briquets of desirable size, preferably in the shape of polygonal i blocks.

I-Ieretofore in burners for pulverized fuel the powder itself has been stored in a suitable hopper and fed into an ainstream. The danger of explosion taking place in the feedhopper is ever present in such apparatus and on that account constant attention from a skilled operator is essential, which fact together with the element of danger from explosion has rendered this type of burner impractical for Small furnaces including those employed for domestic heating purposes'.

Coal in briquet form is, of course, not explosive, and with that fact in mind I have designed the present machine which is adaptand composition are uniform throughout, rey moving the fuel from the briquet in particles of the proper degree of ineness for perfect combustion, thus eliminating liability of a dangerous explosion because only a very small quantity of pulverized fuel is present in the apparatus at any time.

The general object of the invention therefore is the provision of an apparatus for removing fuel in fine particles from a briquet, mixing the powdered fuel thoroughly with air and feeding the mixture into a furnace.

Subsidiary objects are the provision of means for regulating the rate of removal of the fuel particles from the briquet, `means for guarding against damage to the apparatus by minor explosions in the mixing chamber, A the provision of a briquet hopper or container which moves with respect to the cutter so as' to present constantly changing surfaces to the action of the cutter, the provision of means for delaying the action of the hopper moving means until the cutter is in operation application, I have illustrated in the accompanying drawings in which: l v

Fig. 1 is an end elevation of an apparatus embodying my invention.

Fig. 2 is a vertical section taken transversely through the apparatus at about the center of the briquet container or magazine, and on the line 2 2 of' Fig. 3.

Fig. 3 is a vertical, longitudinal section taken on the line 3 3 of Fig. 1.

Fig. 4 is a horizontal, sectional view taken substantially on the line 4 4 of Fig. 3. 70

.Figl 5 is a view in plan of thecomplete machine on a smaller scale.

Fig. 6 is a-detail view vof the blower employed in the apparatus, the view being a section taken substantially on the line 6 6 75 of Fig'. 3 but showing the blower fan in elevation.

F-ig. 7 is an elevation of a beater which I may employ, the view being taken on the line 7 7 of Fig. 3.

Fig. 8 is a detail elevation of one of the fixed elements of the beater.`

Fig. 9 is a detail of one of the rotating elements of the beater.

Fig. 10 is a detail sectional view taken sub- 85 stantially on the line 10 10 of Fig. 4 and showing a centrifugal clutch operating mechanism.

Like referencecharacters refer to like parts throughout the views. p

In the drawings, .10 represents a base of generally rectangular form provided with inset bosses 11 containing bolt holes 12 by means of which the base may be secured to a floor in close proximity to the burner to be fired. The various other parts of the apparatus are supported upon the base and attached thereto in any suitable manner.

The apparatus as illustrated in the drawings comprises a magazine' or briquet con-.160

beater and a blower.

tainer, a pulverizer and mixer, a gear box, a The magazine or briquet container, numbered 13 on the drawings, which is preferably made of sheet metal, consists of a relatively long, preferably rectangularcontainer open at both ends and having its corners rounded more or less. The magazine is preferably arranged vertically so that the briquets will be fed therethrough by gravity. As illustrated, the container is adapted for the reception of cubical briquets, but of course it may be sov designed as to receive briquets of other shapes, the latter being preferably polygonal, however, in order that the rotation of the container may be readily comlnunicated to the'briquets. As its lower end the container 13 is mounted in a casting 14 to which is secured a ring worm gear 15 by means of which rotation is imparted to the container, as will hereafter ape pear.

The casting 14 is mounted to revolve or rotate upon a circular track 16, a replaceable ring or washer 17 being interposed to take wear. The track 16 is integral with the casing 18 of the pulverizer. In one end of this casing there is a circular opening into which is fitted a projection 19 on a cylindrical extension 20 of the gear box 21, this gear box and extension being secured to the pulverizer casing 18 by means of stud bolts 22 extending through bolt holes in a flange 23 on the extension 20 and threaded into holes in the casing 18. Y d

` At the opposite end of the casing 18 there is a blower casing 24, preferably made in two parts fastened together with screws 24. This blower casing carries a ball bearing 25 adapted to take both thrust and radial load the outer race of the bearing being clamped between the casing 24 and flanged oil retainer 26. The bearing is employed for the mounting of the main shaft 27 of the apparatus, which shaft is provided with a reduced portion 28, and a nut 29 for holding the inner race of the bearing in fixed position on theshaft. The relatively small diameter end portion 30 of the shaft runs in rings 31 of felt or the like, which serve to retainthe lubricant, and is connected through a flexible oint 32 of any desired form with an electric motor 33. The electric motor is a convenient source of 'power for a machine of this type, but it is of course to be understood that other means `for supplying" power may be substituted, if

' abuts against another sleeve39. The inner race of bearing 35fis clamped between sleeve 39 and nut 40 threaded onto the end of the shaft. The outer races of both of the bearings 34 and 35 are free to move in their bearing supports lengthwise of the shaft. The nut 40 is located in a cavity 41, in the gear box casing, which is closed against the escape of lubricant by a threaded plug 42.

The Worm 38 meshes with a comparatively large worm whee143 keyed to a shaft 44 running transversely of the machine and supported at'its ends in suitable bearings 44 in the casing 21. On one side the gear 43 carries a pair of lugs 45 which support short shafts 46 to the ends of which are pinned bellcrankplevers 47 having weights 48 carried jointly at the outer ends of each pair of levers, which weights are grooved to receive a coiled spring band 49. The other arms 50 of the bell-cranks 47 engage trunnions 51 on a sleeve 52 which is mounted to slide upon the shaft but splined to turn therewith as shown in Fig. 10. The sleeve 52 carries one element 53 of a clutch, the other element 54 of which is formed on the hub of a spiral 'gear 56 which is rotatable on shaft 44 but held against axial movement thereonand meshes with a spiral geara57 mounted on a shaft 58, near the lower extremity of the latter. Near its upper end the shaft 58 carries a worm 59 which meshes with a Worm wheel 60 on a horizontal shaft 61 which is mounted at its lends in the gear box 21 above the shaft 44, being provided at one end with a ball thrust bearing 62. The shaft 61 has keyed thereto a worm 63 which is arranged to mesh with the worm ring gear 15 by means of which the briquet container 13 is revolved. From the foregoingdescription of the gearing for the apparatus it will be apparent that the gear reduction from the shaft 27 is very great. As a matter of fact the speed of travel of the briquet container in the ordinary operation of the apparatus is only about one revolution per minute.

shown herein, any suitable form of gearing to produce the same result being within thel spirit of the invention.

Now referring to the fuel pulverizing portion of thel apparatus, 64 is the sleeve or hub of the cutter, being splined on the shaft 27, as shown in Fig. 3, and having at one en d and at a position intermediate of its ends plates or spiders 65 and 66, the plate 66 containing a series of perforations 67. Cutter blades 68 are secured at their ends to the spiders `65 and 66 so as to form a tapered rotary cutter. The wcutter blades 68, besides the functionV of removing the particles of `fuel` from the briquet, also have the fu tion of agit-ating these particles and mixin them with air. The cutter is located directly below and in line with a vslot 69in the top of the pulverizer casing, see Figs. 2 and 5, and the blades are-so inclined that the cut.in the' briquet made by them has the same inclinationv as thefslope of the floor- 'cant out of the pulverizing chamber, and

also keeping the pulverized fuel out of th bearing 34 and the gear casing 21.

At the end of the sleeve 64 there is a groove l 72 which receives pins 73 on the bifurcated end portion of a lever 74 which is pivoted at Y 75 upon a bracket 76 secured to the extension 20, the lever 74 at its outer end carrying a swivel block through which a rod 76 loosely slides, the rod 7 6"'calrrying a knurled nut 77 having a flange 78 working under a hook 79 onthe swivel block. The rod 7 6 is pivoted to swing about a center. 8O on a bracket 81, andthe swivel block may be.

locked in any adjusted position by means of a lock screw 82. It will be` apparent that movement of the cutter to the left, as viewed in Figs. 3 and 4, will cause it to take a deeper cut in the briquet.

At the righ -hand endof the pulverizer casing, as viewed in Figs. 3 and 4, is located the beater or agitator, which comprises a series of stampings 83 and 84 shown in detail in Figs. 8 and 9. The stampings 83 are separated by rings or washers 85-and a wider ring 86, and the stampings and rings are all perforated to receive machine screws 87 by means of which these parts are assembled and secured to the casing 18. The stampings and rings together form the cylindrical wall of the beater. The ring 86 is perforated at intervals throughout its periphery to receive screws 89 which are threaded into the blower housing 24, thus forming a secure attachment for the latter and assisting in providing an air-tight joint. Fig. -7 show-s the arrangement of the stampings 83 as to their 'angular positions. In this case four such stampings are employed, lthe two at the ends having their blades positioned vertically while the two intermediate ones are positioned so as to bring their blades into lines at 60o intervals from each otherand from those of the end plates.

On the shaft 27 at points opposite the rings 85 and,86 are mounted three stampings 84 which are keyed to the shaft at 60o intervals, the stampings being separated by washers 90 of a thickness equal to that of the rings 85 and 86, the washers and rings being slightly thicker than the stampings so as to provide clearance between the stationary and moving beater blades. The use of an agitator or beater of the character just described is deemed advisable, but I do not consider that this or any other type of beater, in addition to the cutter,'is essential to the invention, as-the cutter, particularly in the form which I have'described, serves to agitate the particles of fuel and mix them with air.

The blower fan .has a slightly` elongated hub 91 which serves to hold the rotating stampings 84 and their supporting washers 90 against a shoulder'92 on the shaft. The

other end of the hub 91 bears against the inner race of the ball bearing 25. Packing 93 pre` vents oil from the bearing 25 from working into the blower casing. The blades of the blower are indicated at 94 in the drawings, and the exit from the blower which is intended to be connected to the furnace, \to be fired, is marked 95.

Air is admitted to the pulverizer casing through a passage 96 located laterally of the cutter, which passage is controlled by some form of shutter or damper, that disclosed in the drawing consisting of a fixed shutter 97 and a movable shutter 98 which is connected with the lever 74 by a link 99, whereby the adjustment of the shutter 98 is simultaneous with the adjustment of the cutter sleeve 64 upon its shaft, so as to increase or decrease the quantity of air in accordance with varitions in the rate at which the fuel is cut from the briquets. i

In the wall of the casing 18 opposite the air passage 96 there is a pressure release opening 100 normally closed by a plate 101, the latter being held in a closed position by coil Springs 102 which bear upon the plate at their inner' ends and at their' outer ends upon washers and nuts 104 carried by studs 103 mounted in-the casing, the plate 101 being slidable on the studs 103 and the tension of the closing springs being adjustable by means of the nuts to regulate the pressure required for opening the closure. The opening also permits access to thecutter blades 68, for the purposeiof removing and replacing them, when the plate 101 is removed.

0pemtfiom-The magazine 13 is to be filled with briquets of coal of sectional dimensions to loosely fit the magazine, the briquets being placed one upon another to a. height suflieient to supply the fuel required for the given period of time. The adjusting nut 77 is operated to provide the required air opening between the shutters 97 and 98 and the proper adjustment lof the cutter. This adjustment will generally be changed only at infrequent intervals, and need not necessarily be changed vat all, as a constant temperature may be maintained in the heated rooms by starting and stopping the apparatus as required, the invention lending itself readily to automatic therinostatic regulation.

' Then the motor 33 is started the shaft 27, being directly connected thereto, immediately rotates the cutter, the rotary parts 84 of the beater and the blower fan. The cutter removes the small amount of i'uel with which its blades come in contact and this is thoroughly mixed with air by the blades 68, the blades of the heater and by the blower, and carried out of ,the apparatus and into the burner and thence to theV furnace by the action of the blower. The amount-of fuel so moved is practically negligible as there is no feed of the briquet to the cutter. As soon as the shaft 27 and the shaft 44 driven thereby get up to speed, however, centrifugal force acting on the weights 48 against the action of spring 49 rocks the short shafts 46 in their bearings in the brackets 45 and causes' the crank arms. 50, acting through the pins 5l, to shift sleeve 22 with its clutch element 53 along the shaft 44 until the clutch element 54 is engaged and thus rotation is imparted to spiral gear 56. Owing to the considerable speed 'reduction through main gearing A38 and 43, the shaft 44 does not revolve rapidly, and hence the movement of the clutch members into engagement does not ycause any appreciable shock., Rotary motion is then transmitted to the magazine 13 from gear 56, through gears 57 and 59 on shaft 58, gears 60 and 63 on shaft 6l and large Worm ring gear 15 on the casting 14 at the bottom of the container. Very slow motion is thereby imparted to the container and the cutter becomes effective.

Air entering through the passage 96 flows between the blades 68 of the cutter into the int ior thereof and out through the holes 67 in t e end plate 66 of the cutter, making a right-angled turn in so doing. The line particles of fuel removed by the rapidly rotating `blades 68 are taken into suspension by the air thus moving through the cutter, the air and fuel being considerably agitated by the movement of the blades and by the change in direction of the moving air, with the result that an intimate mixture of air and fuel particles is accomplished.

This mixture then passes through the beater heretofore described, if a beater is emff ployed, being thus further agitated and a more thorough mixture being obtained. The mixture leaving the beater enters the blower casing where it is acted upon by the fan blades 94 which moveit rapidly outward and through the spiral passage of the blower. Here too there is a mixing effect. Consequently, when the mixture leaves the blower and flows out through the passage 95 to the furnace itis in an ideal state for combustion, assuming that the apparatus has been adjusted to provide the proper proportions of air and fuel dust.

I claim as my invention:

1. In apparatus of the class described, means for holding a briquet and scraping fuel therefrom in fine particles, means for mixing said particles with air, and means for feedingthe mixture to a burner.

2. In apparatus of the class described, means for holding a briquet, means for removing fuel therefrom in fine particles, means for mixing said particlesl with air, means under a single control for regulating the rate of removal of such particles and the amount of air to be mixed therewith so as to vary the quantity of the mixture while maintaining a predetermined proportion in the mixture, and means vfor feeding the mixture to a burner. I

3. In appara-tus" of the class described, means for removing fuel in fine particles from the surface of a briquet, means for moving the briquet so as to present different portions thereof to the action of said fuel removing means, means for mixing said particles with air, and means for feeding the mixture to a burner. e

4. In apparatus of the class described, rotary means for removing fuel in fine particles from-the surface of a briquet, means for rotating the briquet around an axis substantially at right angles to said rotary means for presenting constantly changing surfaces to the action of said rotary means, means for mixing said particles with air, and means for feeding the mixture to. a burner.

5. In apparatus of the class. described, means adapted to contact with a portion only of one surface of a briquet for removing fine particles therefrom, means for moving the briquet so as to present constantly changing portionsof said surface. to the action of said particle removingmeans, means for mixing said particles with air, and means for feeding themixture to a burner. v i

6. In apparatus of the class described, a briquet feeder', a rotary cutter arranged to produce a cut at an obtuse angle to the direction of feed, means for producing relative motion between said feeder and said cutter in the general direction of the Caxis of the cutter, whereby the depth of cut is regulated, means for mixing said particles with air, and means for feeding the mixture to a burner.

7. In apparatus of the class described, a briquet feeder, a rotary cutter mounted to turn about an axis at right angles to the disaid axis, means f or producing relative motion between `said feeder and said cutter in the direction of said axis, whereby the depth of cut is regulated, means for mixing said particles with air and means for feeding the mixture to a burner.

'8. In apparatus of the class described, a briquet feeder, means for removing fuel from the briquet in fine particles', a chamber in which sai-dy means is located, said chamber having an air entrance opening and a mixture exit opening, and a further opening normally covered by a spring pressed closure adapted. to open outsvardlyin the event of ar. e explosion in the chamber.

9. In apparatus of the classv .described` means for removing fuel 1in ine'particles from the A'surface of briquets, mechanical means for feedinga briquet to said fuel re? moving means, means for causing the fuel Arection of the briquet feed, the cutter being designed to produce a cut at a slight angle to removing means to begin its movement prior to the movement of the said'feeding means, and means for mixing said fuel particles With air and feeding the mixture to a burner.

10. In apparatus of the class described, means\for removing fuel in fine particles from thek surface of briquets, mechanical means for feeding a briquet to said fuel removing means, means for delaying the operation of said feeding means until the said fuel removing means has reached a predetermined speed, and means for mixing said fuel particles with air and feeding the mixture to a burner.

11. In apparatus of the class described, a briquet magazine of non-circular cross section adapted to receive the briquets in series.

- rotating means arranged at one end of said magazine adapted to remove fuel from the briquets in tine-particles, means for turning the magazine so as to present constantly changing portions of the briquet to the action of said rotating means, and means for mixing said fuel particles with air and feeding the mixture to a burner.

12. In apparatus of the class described, a cutter for removing fuel from briquets in fine particles, mechanical means operatively connected thereto for feeding a briquet to said cutter, said latter means being driven through a centrifugal clutch whereby its action begins subsequent to the action of said cutter and discontinues prior to the discontinuance of the action of said cutter, and means for mixing said fuel 'particles with air and feeding the mixture Yto a burner.

13. In apparatus of the class described, a briquet feeder, a easing in communication with the delivery end of said feeder. a shaft in said easing arranged transversely to the' axis of the feeder, means on said shaft adapted by rotationrto remove fine particles from the surface of a briquet in said feeder,v

the periphery of saidmeans being inclined with respect to said shaft, said particle removing means being adjustable along the axis of said shaft, said casing having an air intake opening, a damper for controlling the movement of air through said opening, and .common means for adjusting said particle removing means and for operating said damper, whereby the quantity of fuel particles removed and the amount of air for the mixture are simultaneously controlled, and means for feeding the mixture to a burner.

14. In apparatus of the class described. a chamber, a briquet feeder in communication with said chamber, rotary means in said chamber for removing fuel in fine particles from the surface of a briquet, means for admitting air to said chamber, a blower for inducing circulation of air therethrough, means arranged in the path ofthe air beyond said rotary means f or agitating the mixture of air and fuel particles, and a conduit for land a blower for moving air therethrough,

thereby taking said particles into suspension, said blower also moving the mixture through said beater, whereby it is agitated and more thoroughly mixed.

16. In apparatus of the classldescribed,

means for holding a briquet, means for removing fuel in fine particles from the surface thereof, means for mixing said particles With air, and means for feeding the mixture to a burner.

17. In apparatus of the class described, means for holding a briquet, means for removing fuel in fine particles from the surface thereof, means for regulating the rate of such removal, means for mixing said particles with air, means for feeding t-he mixture to a burner. Y

18. In apparatus of the class described, means for holding a briquet, means lfor removing fuel in fine particles from the surface thereof, means for mixing said particles With the regulated proportion of air, and means for feeding the mixture to a burner.

19. In apparatus -of the class described, means for holding a briquet, means forremoving fuel in fine particles from the surface thereof, means for mixing said particles With air, means for regulating the rate of removal of such particles, and the amount of air Vmixed therewith, and means for feeding the mixture to a burner.

20. In apparatus of the class described, a briquet holder, a chamber, a rotary means therein for removing fuel in fine particles from the surface of a briquet in said holder, means for directing air through said chamber so as to be mixed With said particles, and means for feeding the mixture to a burner.

21. In. apparatus of the class described, a briquet holder, a chamber, a cutter therein comprising spaced spiders and a plurality of blades supported thereon leaving the interior of the cutter partially open, said cutter by rotation being adapted to remove fuel in line particles from the surface of a briquet in said holder, means for causing air to enter the chamber, whereby said particles are agitated and mixed with the air, and means for feeding the mixture to a burner.

22. Inf apparatus of the class described, a briquet holder, a chamber, a rotary cutter therein comprising spaced spiders and a plurality of blades supported thereon leaving the ibo interior of the cutter partially open, said cut- I hlder,\means comprising saidl chamber for causing a draft of air through said cutter and for turning the air through an angle of approximately 90 during its travel through the cutter, whereby said particles are agitated `and mixed with air, and means for feeding the mixture to a burner.

23. In apparatus of the class described, a briquet holder, a chamber, a cutter compris- 10 ing spaced spiders and aplurality of blades supported thereon leaving the interior of the cutter partially open, said cutter being mounted to rotate in said chamber and being adapted to remove fuel in fine particles from the surface of a briquet in said holder, means for causing air to enter said chamber in one direction and leave it in a. direction substantially at right angles thereto, whereby said particles are agitated and mixed with air,

and means for feeding the mixture to a burner.

24.' In apparatus of the class described, a briquet feeder, a shaft at right angles to the axis of said feeder, a rotary means lmounted to slide upon said shaft and turn therewith for removing fine particles from a briquet in said feeder, the peripheral path of movement of said means being arranged at a. slight angle to said shaft, means for adjusting said means 3o longitudinally upon said shaft for regulating the depth of cut, means for mixing the fuel particles removed from the briquet with air, and means for feeding the mixture to a burner.

25. In apparatus of the class described, a briquet holder,'a' chamber, a rotatable cutter therein comprising spaced spiders and a plu' ra-lty of. blades supported thereon leaving the interior of the cutter partially open, said cut- 40 ter being adapted to remove fuelin fine particles from the surface of a briquet in said l1older,means for causing air to enter said chamber in a direction transverse to the axis of said cutter, whereby said particles are agitated and mixed with air, and means for feeding the mixture to a burner.

26. In apparatus of the class described, a briquet holder, a casing, means for admitting air thereto, a rotary means in said casing for removing fuel in ine particles from the surfaceof a briquet in said holder, said rotary means being mounted to rotate in the path of the admitted air whereby the particles removed from the briquet are agitated and mixed with air, and a blowerfor producing a current of air through said casing past said rotary means and into a burner.

In testimony whereof, I hereunto aflix my signature.

so LEE B. GREEN. 

